1. Technical Fields
The present invention relates to a sheet material feeding device and a recording apparatus.
2. Related art
As a recording apparatus configured to record characters or images on various sheet materials such as paper, cloth, film, for example, a copying machine, a printer, and a facsimile are exemplified. The recording apparatus of this type includes a sheet material feeding device configured to separate a single sheet material from a stacking portion (supporting portion) that supports a plurality of the sheet materials in a stacked manner and feed the separated material to a recording unit configured to perform a recording process. The sheet material feeding device includes a separating unit having a separating bevel inclined at a predetermined angle with respect to a sheet material supporting surface and configured to separate the sheet materials fed toward the separating bevel by a pickup roller one by one separately by applying a load (including a reaction force and a frictional force) in the direction opposite from a feeding direction against the sheet materials which come into abutment with an inclined plane of the separating bevel in order to prevent double feed (multiple feed) which feeds two or more sheet materials simultaneously as described in JP-A-11-11719.
In recent years, there are a variety of types (material quality, size, thickness, etc.) of the sheet materials which is available for a recording process. Therefore, a mode to store a plurality of types of the sheet materials in a stack portion and separate the plurality of types of sheet materials using a common separating unit is employed. However, the sheet materials of different types are different in rigidity. Therefore, the separating bevel in the related art has a problem such that application of loads suitable for the separation of the sheet materials according to their rigidities is difficult.
In general, in order to avoid the double feed of papers having low rigidity such as normal papers, it is required to make the angle of the inclined plane steeper to increase the load applied at the separating bevel. However, in the case of papers having high rigidities such as photo papers or post cards, when they come into abutment at the steeper angle, the load (reaction force) acts strongly on these papers and, consequently, slippage may occur between a pickup roller and the papers and hence a phenomenon such that feeding of paper is disabled, so-called a non-feed phenomenon may easily be caused. In other words, since the photo paper for example has high rigidity, the photo paper hardly achieves buckling (flexure, bending) deformation at the separating bevel and hence it is difficult to be fed along the inclined plane.
In contrast, there is a method of reducing the angle of inclination of the inclined plane to reduce the load of the separation bevel in order to separate and feed the papers with high rigidity such as the photo paper adequately. In this method, however, the load which acts on the normal paper is in turn reduced, and hence a required load for the separation cannot be obtained at the separating bevel, which may result in the double feed. Alternatively, there is a method of allowing the paper to be deformed easily by increasing the distance between the separating bevel and the pickup roller in order to separate and feed the papers with high rigidity such as the photo paper adequately. In this method, however, the papers having low rigidity are easily deformed as well, and hence a required load for the separation cannot be obtained at the separating bevel, which may result in the double feed. Both of these methods are suffered from the problem of upsizing of the apparatus.